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This paper presents an overview of the evolution & revolution of automotive E/E architectures and how we at Bosch, envision the technology in the future. It provides information on the bottlenecks for current E/E architectures and drivers for their evolution. Functionalities such as automated driving, connectivity and cyber-security have gained increasing importance over the past few years. The importance of these functionalities will continue to grow as these cutting-edge technologies mature and market acceptance increases. Implementation of these functionalities in mainstream vehicles will demand a paradigm shift in E/E architectures with respect to in-vehicle communication networks, power networks, connectivity, safety and security. This paper expounds on these points at a system level.

Low-pressure cooled EGR (LP-cEGR) systems can provide significant improvements in spark-ignition engine efficiency and knock resistance. However, open-loop control of these systems is challenging due to low pressure differentials and the presence of pulsating flow at the EGR valve. This research describes a control structure for Low-pressure cooled EGR systems using closed loop feedback control along with internal model control. A Smith Predictor based PID controller is utilized in combination with an intake oxygen sensor for feedback control of EGR fraction. Gas transport delays are considered as dead-time delays and a Smith Predictor is one of the conventional methods to address stability concerns of such systems. However, this approach requires a plant model of the air-path from the EGR valve to the sensor.

The Indicated Mean Effective Pressure (IMEP) is a very important engine parameter, giving significant information about the quality of the cycle that transforms heat into mechanical work. For this reason, modern data acquisition systems display, on line, the cylinder pressure variation together with the corresponding IMEP. The paper presents a very simple algorithm for the calculation of IMEP, based on the correlation between IMEP and the gas pressure torque. It was found that that the IMEP may be calculated by a very simple formula involving only two harmonic components of the cylinder pressure variation. The computation of the two harmonic components is very easily performed because it does not involve the calculation of an average pressure and the cylinder volume variation. The method was experimentally validated showing differences less than 0.2% with respect to the IMEP calculated by the traditional method.

A flow network method was developed to predict the underhood temperature distribution of an automobile. The method involves the solution of simplified energy and momentum equations of the air flow in control volumes defined by subdividing the air space between the surfaces of the underhood components and the front-end geometry. The control volumes are interconnected by ducts with branches and bends to form a flow network. Conservation of mass and momentum with appropriate pressure-loss coefficients leads to a system of algebraic equations to be solved for the flow rates through each volume. The computed flow rates are transferred to a thermal model to calculate the temperatures of the air and the major vehicle components that affect the underhood environment. The method was applied to a 1986 3.0L Taurus and compared with vehicle experiments conducted in a windtunnel.

Today, 99% of the two wheelers in India operate with carburetor based fuel delivery system. But with implementation of Bharath Stage VI emission norms, compliance to emission limits along with monitoring of components in the system that contributes towards tail pipe emissions would be challenging. With the introduction of the OBD II (On-Board Diagnostics) and emission durability, mass migration to electronically controlled fuel delivery system is very much expected. The new emission norms also call for precise metering of the injected fuel and therefore demands extended calibration effort. The calibration of engine management system starts with the generation of pre-calibration dataset capable of operating the engine at all operating points followed by base calibration of the main parameters such as air charge estimation, fuel injection quantity, injection timing and ignition angles relative to the piston position.

A new three-dimensional human head finite element model, consisting of the scalp, skull, dura, falx, tentorium, pia, CSF, venous sinuses, ventricles, cerebrum (gray and white matter), cerebellum, brain stem and parasagittal bridging veins has been developed and partially validated against experimental data of Nahum et al (1977). A frontal impact and a sagittal plane rotational impact were simulated and impact responses from a homogeneous brain were compared with those of an inhomogeneous brain. Previous two-dimensional simulation results showed that differentiation between the gray and white matter and the inclusion of the ventricles are necessary in brain modeling to match regions of high shear stress to locations of diffuse axonal injury (DAI). The three-dimensional simulation results presented here also showed the necessity of including these anatomical features in brain modeling.

Many approaches have been taken to determine the burning velocity in internal combustion engines. Experimentally, the burning velocity has been determined in optically accessible gasoline engines by tracking the propagation of the flame front from the spark plug to the end of the combustion chamber. These experiments are costly as they require special imaging techniques and major modifications in the engine structure. Another approach to determine the burning velocity is from 3D CFD simulation models. These models require basic information about the mechanisms of combustion which are not available for distillate fuels in addition to many assumptions that have to be made to determine the burning velocity. Such models take long periods of computational time for execution and have to be calibrated and validated through experimentation.

Brake squeal is caused by the friction-induced vibration at the rotor/pad interfaces (primary contact interfaces) in a disc brake system. While there have been numerous research work evaluating the influence of primary contact interfaces on brake squeal, few studies can be found on the effect of the secondary contact interfaces, i.e., outer pad/caliper fingers, inner pad/pistons and pad/abutment, which can also significantly affect brake squeal based on our various dynamometer and vehicle tests. It is therefore the objective of this paper to investigate both the primary and the secondary contact interfaces and their influence on brake squeal. Simplified analytical models are created to gain insight into the stability of the brake system under low and high brake pressure; non-linear FEA analysis is employed for parametric study and countermeasure development; dynamometer and vehicle tests are used for verification.

Lower extremity injuries in frontal automotive crashes usually occur with footwell intrusion where both the knee and foot are constrained. In order to identify factors associated with tibial shaft injury, a series of numerical simulations were conducted using a finite element model of the whole human body. These simulations demonstrated that tibial mid-shaft injuries in frontal crashes could be caused by an abrupt change in velocity and a high rate of footwell intrusion.

Vibration and noise are generally considered to be the major problems in power transmission chains. This paper presents an adaptive, active control strategy for the reduction of vibration in automotive timing chain drives and examines the effects of the active control on noise reduction. Experimental results show that the average vibration amplitude is diminished by as much as 90% under low to moderate tension conditions, and the chain noise is reduced by about 3 dB. The experimental apparatus has low cost and is readily applicable to an industrial environment.

The flow structure inside the catalytic converter of gasoline engines is very important for consideration of the catalyst light-off condition, converter durability and conversion efficiency. However, the available experimental data under actual engine exhaust conditions are quite limited due to its complicated configuration, critical operating conditions and difficult optical access. Therefore, an experimental study was performed, using laser Doppler velocimetry technique, to measure the velocity distributions inside two production dual-monolith catalytic converters fitted on a firing gasoline engine over several engine operating conditions. This paper reports the normal velocity characteristics measured in a plane 1 mm away from the front surface of first monolith. A small fraction of titanium (IV) isopropoxide was dissolved in gasoline for generating titanium dioxide seeding particles during the engine combustion.

Port fuel injection system in gasoline engines is receiving an increasing attention for its potential advantages in meeting the constrains of simultaneous reduction in fuel consumption and exhaust emission, and maintaining a good engine performance. The structure of port injector spray dominates the mixture preparation process and strongly affect the subsequent engine combustion characteristics over a wide range of operating conditions in port-injection gasoline engines. In this paper, an experimental and analytical study is made to characterize the breakup mechanism and atomization process of the non-air-assisted port injector sprays in gasoline engines. The liquid sprays resulted from various types of current and development-type automotive fuel injectors were visualized using planar laser-induced fluorescence imaging technique. A comparison was made on the spray structure of the single hole and multi-hole injectors.

Numerical analyses of head and neck response during side impact are presented in this paper. A mathematical human model for side impact simulation was developed based on previous studies of other researchers. The effects of muscular activities during severe side impact were analyzed with the use of this model. This study shows that the effect of muscular activities is significant especially if the occupant is prepared to resist the impact. This result suggests that the modeling of muscles is important for the simulation of real accident situation.

The use of Low Pressure - Exhaust Gas Recirculation (EGR) is intended to allow displacement reduction in turbocharged gasoline engines and improve fuel economy. Low Pressure EGR designs have an advantage over High Pressure configurations since they interfere less with turbocharger efficiency and improve the uniformity of air-EGR mixing in the engine. In this research, Low Pressure (LP) cooled EGR is evaluated on a turbocharged direct injection gasoline engine with variable valve timing using both simulation and experimental results. First, a model-based calibration study is conducted using simulation tools to identify fuel efficiency gains of LP EGR over the base calibration. The main sources of the efficiency improvement are then quantified individually, focusing on part-load de-throttling of the engine, heat loss reduction, knock mitigation as well as decreased high-load fuel enrichment through exhaust temperature reduction.

Ten pairs of thawed fresh-frozen human cadaveric lower arm specimens were subjected to lateral three-point bending. Either the radius or ulna were impacted with a 4.5 kg dropped weight at approximately 3 m/s or tested quasi-statically in a materials testing machine. Fracture occurred primarily near the loading site with an average dynamic peak load of 1370 N and average peak moment of 89 Nm. Differences between the radius and ulna were not significant. Static fracture load and moments were approximately 20% lower. Sectional and mineral properties of each specimen near the fracture sites were measured.

Side impact pendulum tests were conducted on Eurosid I and Biosid to assess the biofidelity of the thorax, abdomen and pelvis, and determine injury tolerance levels. Each body region was impacted at 4.5, 6.7, and 9.4 m/s using test conditions which duplicate cadaver impacts with a 15 cm flat-circular 23.4 kg rigid mass. The cadaver database establishes human response and injury risk assessment in side impact. Both dummies showed better biofidelity when compared to the lowest-speed cadaver response corridor. At higher speeds, peak force was substantially higher. The average peak contact force was 1.56 times greater in Biosid and 2.19 times greater in Eurosid 1 than the average cadaver response. The Eurosid I abdomen had the most dissimilar response and lacks biofidelity. Overall, Biosid has better biofidelity than Eurosid I with an average 21% lower peak load and a closer match to the duration of cadaver impact responses for the three body regions.

Robert Bosch LLC North America has developed and calibrated an engine management system for gasoline direct injection engines. This system controls the General Motors 3.6L DOHC 4 valve V6 engine which features direct injection, variable valve timing and electronic throttle control. This engine powers the 2008 model year Cadillac CTS and STS. It is the first GM production direct injection V6 engine in North America. It produces 304 HP at 6500 rpm and 370 Nm torque at 5200 rpm. Emissions meet LEV2 Bin5 standards. Interesting features include wall guided direct fuel injection, homogeneous split injection for fast catalyst light off and one of the industry's first isolated injection systems for noise reduction. This paper provides an overview of the features of this system and focuses on the calibration development.

Relative motion between the brain and skull may explain many types of brain injury such as intracerebral hematomas due to bridging veins rupture [1] and cerebral contusions. However, no experimental methods have been developed to measure the magnitude of this motion. Consequently, relative motion between the brain and skull predicted by analytical tools has never been validated. In this study, radio opaque markers were placed in the skull and neutral density markers were placed in the brain in two vertical columns in the occipitoparietal and temporoparietal regions. A bi-planar, high-speed x-ray system was used to track the motion of these markers. Due to limitations in current technology to record the x-ray image on high-speed video cameras, only low- speed (﹤ 4m/s) impact data were available.

Ion current sensors have been considered for the feedback electronic control of gasoline and diesel engines and for onboard vehicles powered by both engines, while operating on their conventional cycles or on the HCCI mode. The characteristics of the ion current signal depend on the progression of the combustion process and the properties of the combustion products in each engine. There are large differences in the properties of the combustible mixture, ignition process and combustion in both engines, when they operate on their conventional cycles. In SI engines, the charge is homogeneous with an equivalence ratio close to unity, ignition is initiated by an electric spark and combustion is through a flame propagating from the spark plug into the rest of the charge.

Because of their robustness and cost performance, multi-hole gasoline injectors are being adopted as the direct injection (DI) fuel injector of choice as vehicle manufacturers look for ways to reduce fuel consumption without sacrificing power and emission performance. To realize the full benefits of direct injection, the resulting spray needs to be well targeted, atomized, and appropriately mixed with charge air for the desirable fuel vapor concentration distributions in the combustion chamber. Ethanol and ethanol-gasoline blends synergistically improve the turbo-charged DI gasoline performance, especially in down-sized, down-sped and variable-valve-train engine architecture. This paper presents the spray imaging results from two multi-hole DI gasoline injectors with different design, fueled with pure ethanol (E100) or gasoline (E0), under homogeneous and stratified-charge conditions that represent typical engine operating points.